Robot end effectors that carry objects

Abstract

Systems and methods are provided for facilitating the operations of an end effector that grasps objects such as baggage. One exemplary embodiment is a system that includes a finger of an end effector of a robot. The finger includes a finger base, a body that extends from the finger base, a first continuous friction belt having an exposed portion along a first side of the body, and a second continuous friction belt having an exposed portion along a second side of the body.

The invention claimed is: 
     
       1. A system comprising:
 a finger of an end effector of a robot, the finger comprising:
 a finger base; 
 a body that extends from the finger base; 
 a first continuous friction belt having an exposed portion along a first side of the body; 
 a second continuous friction belt having an exposed portion along a second side of the body; 
 a motor driving the first friction belt; and 
 a motor driving the second friction belt. 
 
 
     
     
       2. The system of  claim 1  further comprising:
 a controller that drives the first friction belt and the second friction belt. 
 
     
     
       3. The system of  claim 2  wherein:
 the controller advances the exposed portions of the first friction belt and the second friction belt in a direction opposed to motion of the end effector as the end effector moves forward towards an object for grasping. 
 
     
     
       4. The system of  claim 2  wherein:
 the controller advances the exposed portion of the first friction belt in a direction opposed to motion of the end effector as the end effector retracts with a grasped object, while also holding the second friction belt in position. 
 
     
     
       5. The system of  claim 2  wherein:
 for each finger, the controller drives the first friction belt and the second friction belt by an amount corresponding with an amount of motion of the end effector as the end effector moves forward. 
 
     
     
       6. The system of  claim 1  wherein:
 the first friction belt and the second friction belt are operable to be driven concurrently as the end effector moves forward. 
 
     
     
       7. The system of  claim 1  further comprising:
 a stereoscopic camera attached to the end effector. 
 
     
     
       8. The system of  claim 1  further comprising:
 a backing plate that separates the exposed portion of the first friction belt from an opposite side of the first friction belt. 
 
     
     
       9. The system of  claim 1  wherein:
 the end effector further comprises: 
 an end effector base; and 
 the finger is one of multiple opposed fingers that are coupled with the end effector base and are operable to move towards each other to tighten a grip on an object. 
 
     
     
       10. The system of  claim 9  further comprising:
 rigid linkages that each extend from the end effector base, each linkage operable to pivot about the end effector base, 
 wherein the finger is attached to a corresponding linkage, and each finger is operable to pivot about the linkage to which it is attached. 
 
     
     
       11. The system of  claim 10  further comprising:
 a controller that directs the linkages to pivot about the end effector base causing the fingers to move towards each other. 
 
     
     
       12. The system of  claim 9  further comprising:
 a controller that repositions the end effector by directing a kinematic chain of actuators and rigid bodies attached to the end effector. 
 
     
     
       13. The system of  claim 9  wherein:
 the end effector further comprises a coupling that rotates the end effector base. 
 
     
     
       14. The system of  claim 9  further comprising:
 an imaging system that provides input for operating the end effector. 
 
     
     
       15. A method comprising:
 for each of multiple fingers of an end effector as the end effector moves forward towards an object:
 driving a first friction belt along a first side of the finger causing an exposed portion of the first friction belt to advance in response to motion of the end effector; and 
 driving a second friction belt along a second side of the finger causing an exposed portion of the second friction belt to advance in response to motion of the end effector. 
 
 
     
     
       16. The method of  claim 15  further comprising:
 drawing the fingers together to form a grip on the object. 
 
     
     
       17. The method of  claim 15  wherein:
 driving the first friction belt causes the exposed portion of the first friction belt to advance in response to motion of the end effector; and 
 driving the second friction belt along the second side of the finger causes the exposed portion of the second friction belt to advance in response to motion of the end effector. 
 
     
     
       18. The method of  claim 15  further comprising:
 identifying the object for retrieval, the end effector comprising an end effector base and opposed fingers that are coupled with the end effector base and are operable to move towards each other to tighten a grip on an object; and
 moving the end effector forward towards the object. 
 
 
     
     
       19. The method of  claim 15  wherein:
 driving the first friction belt and driving the second friction belt comprises:
 driving the first friction belt and driving the second friction belt by an amount corresponding with an amount of motion of the end effector as the end effector moves forward. 
 
 
     
     
       20. The method of  claim 15  further comprising:
 retracting the end effector; 
 driving the first friction belt, advancing the exposed portion of the first friction belt in a direction opposed to motion of the end effector as the end effector retracts; and 
 holding the second friction belt in position as the end effector retracts. 
 
     
     
       21. The method of  claim 15  wherein:
 drawing the fingers together comprises by pivoting linkages that attach the fingers to a base of the end effector. 
 
     
     
       22. The method of  claim 15  further comprising:
 adjusting a distance between the fingers to match a size of the object. 
 
     
     
       23. The method of  claim 22  further comprising:
 holding the fingers parallel with each other spaced wide enough to clear the object to be grasped and parallel with edges of the object as the distance is adjusted. 
 
     
     
       24. A method comprising:
 placing a finger of an end effector between two objects, by:
 driving a first continuous friction belt, via a first motor, along a first side of the finger causing an exposed portion of the first friction belt to advance in response to motion of the end effector, the exposed portion of the first friction belt facing a first of the two objects; 
 driving a second continuous friction belt, via a second motor, along a second side of the finger causing an exposed portion of the second friction belt to advance in response to motion of the end effector, the exposed portion of the second friction belt facing a second of the two objects; and 
 moving the end effector relative to the two objects. 
 
 
     
     
       25. A non-transitory computer readable medium embodying programmed instructions which, when executed by a processor, are operable for performing a method comprising:
 for each of multiple fingers of an end effector as the end effector moves forward towards an object:
 driving a first friction belt along a first side of the finger causing an exposed portion of the first friction belt to advance in response to motion of the end effector; and 
 driving a second friction belt along a second side of the finger causing an exposed portion of the second friction belt to advance in response to motion of the end effector. 
 
 
     
     
       26. An apparatus comprising:
 a rigid frame; 
 an axle rotatably mounted to a base of the frame; 
 wheels attached to ends of the axle; and 
 a finger attached to the base of the frame that protrudes from the base of the frame, the finger comprising:
 a first drivable friction belt having an exposed portion that defines an upper surface of the finger; 
 a second drivable friction belt having an exposed portion that defines a lower surface of the finger; 
 a motor that drives the first friction belt and the second friction belt; and 
 a brake that is operable to halt driving of the first friction belt without halting the second friction belt as the finger retracts backward. 
 
 
     
     
       27. The apparatus of  claim 26 , wherein:
 the motor advances the exposed portion of the first friction belt and the exposed portion of the second friction belt in a direction opposed to motion of the finger as the finger advances forward. 
 
     
     
       28. The apparatus of  claim 27  wherein:
 the brake is operable to hold an upper surface of the first friction belt in position during retraction, while a lower surface of the second friction belt moves opposed to the direction of retraction.